AP Programming Question

[jmcoreymv]

Im using VC++ 6 and Im trying to use the AP String class but when I link it, I get a bunch of unresolved external errors. The compile however is fine. And its a really simple program which im copying out of the lesson so I know its not my code. What causes unresolved symbols and stuff like that?

 

[Platypus]

Post your code here.
Apstring has some weird ass errors sometimes, that usually have nothing to do with the class itself.

 

[tweakmm]

<< Apstring has some weird ass errors sometimes, that usually have nothing to do with the class itself. >>

 

[Gunslinger08]

Just use cstring

Dunno if it's available in VC++, but it works the same in Borland (only thing my crappy school can afford).

Josh

 

[tweakmm]

<< Just use cstring
>>


he's in an AP class

 

[jmcoreymv]

Heres the code:

#include<iostream.h>
#include"apstring.h"
void testConstructors();

int main()
{
testConstructors();
return(0);
}

void testConstructors()
{
apstring word1;
apstring word2("Hello World\0");
apstring word3("Hello World\n");
cout<<"Testing constructors"<<endl<<endl;
cout<<word1;
cout<<word2;
cout<<word3;
}

Heres the errors:

Linking...
strings231.obj : error LNK2001: unresolved external symbol "public: __thiscall apstring::~apstring(void)" (??1apstring@@QAE@XZ)
strings231.obj : error LNK2001: unresolved external symbol "class ostream & __cdecl operator<<(class ostream &,class apstring const &)" (??6@YAAAVostream@@AAV0@ABVapstring@@@Z)
strings231.obj : error LNK2001: unresolved external symbol "public: __thiscall apstring::apstring(char const *)" (??0apstring@@QAE@PBD@Z)
strings231.obj : error LNK2001: unresolved external symbol "public: __thiscall apstring::apstring(void)" (??0apstring@@QAE@XZ)
Debug/strings231.exe : fatal error LNK1120: 4 unresolved externals
Error executing link.exe.

strings231.exe - 5 error(s), 0 warning(s)

 

[tweakmm]

have you ever used the AP classes on this computer before?
Do they work for other programs?

 

[Platypus]

Hmmmm sounds like your compiler doesn't like Apstring. Have you used it before?

 

[Mr.IncrediblyBored]

Try including "apstring.cpp" instead of .h

 

[Platypus]

<< Try including "apstring.cpp" instead of .h >>



No.. apstring is a class. It has to be called like a class. And the class is in the H file.
Try <apstring.h> just for sh|ts and giggles.

 

[tweakmm]

<<

<< Try including "apstring.cpp" instead of .h >>



No.. apstring is a class. It has to be called like a class. And the class is in the H file.
Try <apstring.h> just for sh|ts and giggles. >>


that might help, but he might now have the header/class files in the right directory.
Have you used the AP classes on this computer before

 

[tweakmm]

nobody liked my pun

 

[Platypus]

Yeah, make sure apstring.h is in your compiler's library folder, or you can specify a path for it.

 

[jmcoreymv]

I have used two other ap classes so far, apvector and apmatrix. Both seemed to work fine. The compiler is the one thats part of VC++ 6 as part of Enterprise Edition of VS. I also have the Architect Version of VS NET but I cant figure out how to make that thing compile. The option always stays greyed out. If I use the include<> it still gives the same errors (I have a copy of all the files in the include directory).

 

[cchen]

did you include apsting.cpp in your project? apstring is the only ap class that requires the .cpp file in the project

 

[Mr.IncrediblyBored]

<<

<< Try including "apstring.cpp" instead of .h >>



No.. apstring is a class. It has to be called like a class. And the class is in the H file.
Try <apstring.h> just for sh|ts and giggles. >>


I know full well what a class is. I've had this problem before. Including the .cpp instead of the .h works.

 

[cchen]

It wouldn't work with apstring

 

[crypticlogin]

A really quick skim of google doesn't show any implementations of:

apstring word("text");

but tons of:

apstring word = "text";

Are you sure you're calling it right?

 

[cchen]

the way he has it is correct syntax

 

[Platypus]

I have used apstring for two years and never called a .cpp file. Not once.
Perhaps you are not calling it right.
You need to use the replacement operator:

apstring text = "text";

 

[jmcoreymv]

It looks like including the cpp file instead of the header file worked. How odd is that, but thanks for the help guys.

 

[Platypus]

<< It looks like including the cpp file instead of the header file worked. How odd is that, but thanks for the help guys. >>



I don't know what the hell kind of compiler will accept that kind of call, but it isn't anything I have ever seen, not even on AP's own exam.

 

[jmcoreymv]

The compiler is Microsoft's Visual C++ 6. Its a pretty commonly used program I thought.

 

[tweakmm]

<<

<< It looks like including the cpp file instead of the header file worked. How odd is that, but thanks for the help guys. >>



I don't know what the hell kind of compiler will accept that kind of call, but it isn't anything I have ever seen, not even on AP's own exam. >>


no sh!t.....
leave it to M$ to screw up the impementation of a great language

 

[Mr.IncrediblyBored]

<< It wouldn't work with apstring >>


That's odd, cuz it's worked for me on several occasions, but I guess you guys know better.

Hell, a little project I've been working on at home didn't compile correctly (same/similar errors to what jmcoreymv is having) until I included "apstring.cpp."

Edit:

<< I don't know what the hell kind of compiler will accept that kind of call, but it isn't anything I have ever seen, not even on AP's own exam. >>


I've been under the impession that the #include command simply inserts whatever text is "included" be it from a text file or string literal. It doesn't matter if the text is in a .cpp or .h.

In any case, you are very welcome jmcoreymv.